const HOST="http://127.0.0.1:8081/";

//获取url参数
function GetQueryString(name) {
    var reg = new RegExp("(^|&)" + name + "=([^&]*)(&|$)");
    var a = decodeURI(window.location.search);
    var r = a.substr(1).match(reg);//search,查询？后面的参数，并匹配正则
    if (r != null) return unescape(r[2]);
    return null;
}

function isNull(str) {
    if(str == "" || str == null || str == undefined || str == "null" || str == "undefined") {
        return true
    }
    return false
}

function isNum(str){
    return /\d+/.test(str);
}